Infrastructure is in the news as policymakers face a deadline to pass a new highway bill. President Obama visited the Tappan Zee Bridge yesterday and said that “rebuilding America … shouldn’t be a partisan issue,” and then cast blame on the Republicans.

An op-ed in the Wall Street Journal today indicates that Edwards’ Law of Cost Overruns is an international standard. If a politician says that a project will cost $100 million, it will end up costing $200 million or more.

The importance of infrastructure investment for U.S. economic growth is widely appreciated. But policy discussions often get sidetracked by a debate regarding the level of federal spending. To spur growth, it is more important to ensure that investment is as efficient as possible and that investment responsibilities are optimally allocated between the federal government, the states, and the private sector.

The sudden collapse of a 58-year-old bridge across the Skagit River in Washington state has led to renewed calls to spend more money on American infrastructure. But if that spending comes out of tax dollars rather than user fees and is dedicated to replacing bridges, it will be seriously misplaced.

Politicians and liberal economists get misty-eyed when thinking about grand infrastructure projects. But recent stories in the Washington Post about D.C.-area projects illustrate the realities of government capital investments.

Transportation Secretary Ray LaHood recently said that “America is one big pothole.” President Obama, members of Congress, and pundits often claim that our infrastructure is “crumbling.” The Senate Budget Committee’s new spending plan, for example, uses that word no fewer than ten times in calling for a $100 billion infrastructure package. And in a report released yesterday, the American Society of Civil Engineers gives the nation a grade of D+ on its infrastructure.